The present invention relates to a fluid deflecting assembly.
As one of fluid deflecting assemblies, there is known a fluid logic element the wall adherence type wherein the wall adherence phenomenon is utilized in deflecting the direction of flow of a fluid medium. This wall adherence fluid logic element comprises, as shown in FIG. 1 of the accompanying drawings which illustrates such fluid logic element in a schematic longitudinal sectional view, a supply nozzle 2, defined by a pair of parallel walls 1a and 1b spaced a distance Ws from each other, a pair of curved walls 3a and 3b located at a position downstream of the direction of flow of a stream of air and so shaped as to outwardly diverge from each other in a direction downstream of the flow of the air stream, and a pair of opposed control chambers 4a and 4b positioned downstream of the nozzle 2 and upstream of the curved walls 3a and 3b and on respective sides of an air passage defined between the walls 1a, 3a and 1b, 3b. The control chambers 4a and 4b are respectively communicated with the atmosphere through control apertures 5a and 5b each adapted to be selectively closed and opened in any desired or required manner.
In the construction shown in FIG. 1, where the air stream is desired to be deflected at a relatively wide angle, such as shown by .beta., relative to a direction parallel to the direction A of flow of the air stream passing through the nozzle 2, by developing a pressure differential between the control chambers 4a and 4b, the curved wall 3b to which the air stream adheres incident to the closure of the control aperture 5b (or the curved wall 3a to which the air stream adheres incident to the closure of the control aperture 5a) must be curved to have a relatively great angle of arch while the length L of the fluid logic element as measured from the point at which the air stream emerges outwardly from the nozzle 2 to the point lying in a plane parallel to the exit opening defined between the free ends of the walls 3a and 3b remote from the associated control chambers 4a and 4b, has to be five or six times the width Ws of the nozzle 2.
Moreover, with the fluid logic element of the construction shown in FIG. 1, it is not possible to control continuously the direction of flow of the air stream.
There is also known another type of fluid deflecting assembly having a construction such as shown in FIGS. 2 and 3 which illustrate such fluid deflecting assembly in front elevational and side sectional views, respectively. The fluid deflecting assembly having the construction shown in FIGS. 2 and 3 comprises a nozzle defining structure 6, including top and bottom walls 6a and 6b and a pair of opposed side walls 6c and 6d joined together to provide an air passage of substantially rectangular cross section, and a movable louver constituted by a plurality of elongated blades 7 rigidly mounted on respective shafts 8 each having its opposite ends journalled in the adjacent side walls 6c and 6d. These louver blades 7 are at one end corner pivotally linked together by a link 9 so that when the link 9 is moved linearly, all of the louver blades 7 are simultaneously pivoted about the shafts 8.
In the construction as shown in FIGS. 2 and 3, assuming that air under pressure is supplied into the nozzle defining structure 6 in the direction shown by the arrow C while the louver blade 7 are positioned as shown in FIG. 3 for deflecting the air in a direction substantially downwards as viewed in FIG. 3, the air so supplied is divided into a plurality of currents by the respective louver blades 7 and then deflected in a direction as shown by the arrow D after having impinged upon the louver blades 7. However, one of the air currents flowing through a clearance between the bottom wall 6b and the adjacent, lowermost louver blade 7 tends to flow in a direction parallel to the plane of the bottom wall 6b , as shown by the arrow F, and, therefore, collides with the air currents flowing in the direction D. On the other hand, another air current flowing through the clearance between the top wall 6a and the adjacent, topmost louver blade 7 flows in a straight direction parallel to the plane of the top wall 6a without being deflected by any of the louver blades 7.
With the fluid deflecting assembly having the construction shown in FIGS. 2 and 3, the angle through which the air stream formed by the air currents as they emerge from the nozzle defining structure 6 can be deflected is limited and, in addition, the deflected flow of air cannot be concentrated in one desired or predetermined direction. However, in the construction shown in FIGS. 2 and 3, if the pitch P between every adjacent two of the louver blades 7 is selected to have a relatively small value while the width W of each of the louver blades 7 is simultaneously selected to have a relatively great value, a relatively wide angle of deflection is available, but this in turn is accompanied by an increased resistance to the flow of air through the nozzle defining structure 6, thereby reducing the rate of flow of the air stream as the latter emerges from the nozzle defining structure 6.